LOCATION PUNGOKEPUK              AK

Established Series
SAS/TJR
02/2022

PUNGOKEPUK SERIES


Landscape--mountains, mountain valleys, valleys, drift plains
Landform--swales, outwash plains
Slope--0 to 25 percent
Parent material--colluvium influenced by volcanic ash over drift
Mean annual precipitation--about 1100 mm
Mean annual air temperature--about 0 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--udic
Soil temperature regime--cryic
Soil moisture subclass--typic

TAXONOMIC CLASS: Medial over loamy-skeletal, amorphic over isotic Alic Haplocryands

TYPICAL PEDON: Pungokepuk medial silt loam on a south-facing, linear and concave swale, on a slope of 3 percent at an elevation of 105 m (The soil was moist throughout when described on August 10, 2013.)

Oa--0 to 2 cm; highly decomposed plant material; nonsticky and nonplastic; common very fine to coarse roots; moderately acid (pH 5.8); clear smooth boundary

A/E--2 to 13 cm; medial silt loam, matrix color 90 percent brown (7.5YR 4/2) dry, very dark brown (7.5YR 2.5/2) moist, and 10 percent brown (7.5YR 5/2) dry, dark brown (7.5YR 3/2) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine to coarse roots; moderately acid (pH 6.0); clear smooth boundary

Bs--13 to 51 cm; medial silt loam, matrix color 75 percent brown (7.5YR 5/4) dry, dark brown (7.5YR 3/4) moist, 15 percent brownish yellow (10YR 6/6) dry, dark yellowish brown (10YR 4/6) moist, 5 percent reddish yellow (7.5YR 6/6) dry, strong brown (7.5YR 4/6) moist, and 5 percent brown (7.5YR 5/2) dry, dark brown (7.5YR 3/2) moist; weak coarse subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine to medium roots; 3 percent gravel; neutral (pH 7.0); abrupt smooth boundary

2BC--51 to 74 cm; very gravelly sandy loam, brown (10YR 5/3) dry, dark brown (10YR 3/3) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine roots; 5 percent fine masses of oxidized iron, dark brown (7.5YR 3/4) moist, clear boundaries; 35 percent gravel and 15 percent cobbles; neutral (pH 7.0); clear smooth boundary

3C--74 to 150 cm; very gravelly sandy loam, dark grayish brown (10YR 4/2) dry, very dark brown (10YR 2/2) moist; massive; soft, very friable, nonsticky and nonplastic; 35 percent gravel; neutral (pH 7.0)

TYPE LOCATION: Dillingham Census Area, Alaska, about 55 km west-northwest of the city of Dillingham; latitude 59.2676965 degrees north, longitude 159.2753120 degrees west, datum WGS 84 (coordinates determined with a GPS)

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--0 to 3 degrees C
Soil moisture control section--dry less than 45 consecutive days in June through October (udic moisture regime)

Layers influenced by volcanic ash
*Thickness--36 to 90 cm
*Phosphorous retention--70 to 100 percent
*Bulk density--0.45 to 0.9 g/cm3
*Ammonium oxalate Al plus 1/2 Fe--3 to 6 percent
*Volcanic glass content--5 to 50 percent

Medial part of particle-size control section
*Ammonium oxalate Si--0.5 to 1.0 percent
*Ammonium oxalate Fe--0.5 to 2.1 percent

Loamy-skeletal part of particle-size control section
*Clay content--2 to 12 percent
*Sand content--25 to 70 percent
*Total rock fragment content--35 to 75 percent
*Sodium fluoride pH--8.4 to 11.6
*Ratio of 1500 kPa water to measured clay--0.6 to 6.0

Oa horizon
Thickness--2 to 10 cm

A/E horizon
Hue--7.5YR, 10YR
Value--2 or 3 moist, 4 or 5 dry
Chroma--1 to 3 moist
Fine-earth texture--medial silt loam, medial silt
Clay content--2 to 12 percent
Reaction--4.5 to 6.0
Total rock fragment content--0 to 30 percent
Gravel content--0 to 30 percent
Cobble content--0 to 10 percent
Thickness--2 to 15 cm
Bulk density--0.45 to 0.9 g/cm3
Phosphorous retention--70 to 100 percent
Volcanic glass content--30 to 60 percent

Bs horizon
Hue--5YR, 7.5YR
Value--3 or 4 moist, 5 or 6 dry
Chroma--4 to 6 moist
Fine-earth texture--medial silt loam, medial very fine sandy loam
Clay content--2 to 12 percent
Reaction--4.5 to 5.9
Total rock fragment content--0 to 30 percent
Gravel content--0 to 30 percent
Cobble content--0 to 10 percent
Thickness--21 to 60 cm
Bulk density--0.5 to 0.9 g/cm3
Phosphorous retention--70 to 100 percent
Volcanic glass content--5 to 40 percent
Extractable aluminum by 1 N KCl--2 to 25 cmol(+)/kg Al3+
Ammonium oxalate Al plus 1/2 Fe--3 to 6 percent

2BC horizon
Hue--10YR, 2.5Y
Value--3 or 4 moist, 5 or 6 dry
Chroma--3 or 4 moist
Fine-earth texture--silt loam, loamy fine sand, sandy loam
Clay content--2 to 12 percent
Reaction--5.0 to 6.5
Total rock fragment content--0 to 50 percent
Gravel content--0 to 50 percent
Cobble content--0 to 20 percent
Thickness--15 to 45 cm

3C horizon
Hue--10YR, 2.5Y
Value--3 or 4 moist, 5 or 6 dry
Chroma--3 or 4 moist
Fine earth texture--sandy loam, silt loam, coarse sandy loam
Clay content--0 to 12 percent
Reaction--5.5 to 7.0
Total rock fragment content--35 to 75 percent
Gravel content--30 to 75 percent
Cobble content--0 to 20 percent
Thickness--more than 5 cm

COMPETING SERIES: None

GEOGRAPHIC SETTING:
Elevation--0 to 900 m
Climate--warm, moist summers; cold, moist winters
Mean annual precipitation--620 to 2100 mm
Mean annual air temperature-- -3.6 to 1.8 degrees C
Frost-free period--70 to 140 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Klak--no redoximorphic features; mountain slopes
Pegati--redoximorphic depletions; aquic conditions; swales of mountains
Nagugun--no redoximorphic features; glaciated plains
Kwethluk--no redoximorphic features; outwash terraces and glaciated plains
Narogurum--occasional ponding; aquic conditions throughout; no andic soil properties; dips of plains
Nigag--no redoximorphic features; mountain slopes

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturation in normal years--below a depth of 50 to 75 cm in April through May, below a depth of 150 cm throughout the rest of the year
Saturated hydraulic conductivity (Ksat)--moderately high or high in the AE and Bs horizons, high or very high in the 2BC and 3C horizons

USE AND VEGETATION:
Use--wildlife habitat, recreation, subsistence
Potential natural vegetation--bluejoint, fireweed, field horsetail, woolly geranium, western oakfern, splendid feather moss, Barclay's willow, Canadian burnet, tealeaf willow, beauverd spirea

DISTRIBUTION AND EXTENT: Ahklun Mountains, Alaska; MLRA 237; large extent

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: WASILLA, ALASKA

SERIES ESTABLISHED: Togiak National Wildlife Refuge, Dillingham Census Area, Alaska; 2019

REMARKS:
Diagnostic horizons and other features in this pedon
*Particle-size control section--zone from 2 to 102 cm
*Ochric epipedon
*Cambic horizon--Bs horizon
*Andic soil properties--zone from 2 to 51 cm
*Redoximorphic iron concentrations--2BC horizon

See laboratory pedon number 13N44524, layer 13N04793, and number 13N0048, layer 13N00124, for Bs horizons that have andic soil properties and amorphic mineralogy.


National Cooperative Soil Survey
U.S.A.